Is PM Justin Trudeau supposed to be subservient to royalty as his superior (the royalty who lives in palaces & castles in England)?

Yes, as she appointed him and can sack him. Or rather the Governor General did, as her representative. Of course the Governor General chose the leader of the biggest party in the House of Commons, because that's the only way you'll get a stable government. So there's no real choice, but someone has to make the appointment.

However, the Queen knows her place. She will not interfere with the elected government if at all possible, even if the constitution allows her to. She knows British history only too well! The last time a King of England tried it, the result was civil war, he lost and got executed. Technically illegally as he didn't approve the court that tried him, but when his opponents controlled the army, who's gonna argue?

So the Governor General will always give Royal Assent to laws passed by Parliament. Really the role of the head of state in a constitutional monarchy is to be there and do the limited number of things she HAS to do, such as calling elections when the PM asks for one and appointing the PM, which in some republics is done by a relatively powerless ceremonial president. As the head of government, the PM has a definite role of his own and the Queen won't interfere with that.

But if anyone thinks Her Majesty is totally powerless, they are wrong and she does have her uses. As a strategic nuclear weapon in a dress. In Australia in 1975, Parliament couldn't agree a budget and the country was on the verge of government shutdown. The Governor-General used his powers to sack the Labor PM and appoint his National Party opponent on condition that he asked for an immediate general election. Which of course he did as that was why he engineered the situation in the first place. Problem solved.

Oh look, a retarded anonymous monarchy troll.

* yawn * My my, how original.

No, the nominal head of Canada is the Governor General. There is no subservience.

I'm he is polite in the proper way. I doubt he'd touch her butt, the way one Ozzie PM did.

Yes and no. His constitutional position is reliant on The Queen 'allowing' him via the Governor General, to be in the position of PM.

Her role, according to Canadian law is to act on his advice in the best interests of Canada (those duties carried out by the Govenour General.

You can always swap the queen for DT

....and houses. And work harder than most of the world populace.

Peace.

No, dear. No one's required to be "subservient". Respectful to the Queen, yes, but then, the Queen is respectful to heads of government in her turn.

She enjoys social precedence, but he enjoys the power.

No.canada is a independent sovereign nation.

No. Maybe 400 years ago but not now.